Kirigami Patterning of MXene/Bacterial Cellulose Composite Paper for All‐Solid‐State Stretchable Micro‐Supercapacitor Arrays

Abstract

Stretchable micropower sources with high energy density and stability under repeated tensile deformation are key components of flexible/wearable microelectronics. Herein, through the combination of strain engineering and modulation of the interlayer spacing, freestanding and lightweight MXene/bacterial cellulose (BC) composite papers with excellent mechanical stability and a high electrochemical performance are first designed and prepared via a facile all‐solution‐based paper‐making process. Following a simple laser‐cutting kirigami patterning process, bendable, twistable, and stretchable all‐solid‐state micro‐supercapacitor arrays (MSCAs) are further fabricated. As expected, benefiting from the high‐performance MXene/BC composite electrodes and rational sectional structural design, the resulting kirigami MSCAs exhibit a high areal capacitance of 111.5 mF cm −2 , and are stable upon stretching of up to 100% elongation, and in bent or twisted states. The demonstrated combination of an all‐solution‐based MXene/BC composite paper‐making method and an easily manipulated laser‐cutting kirigami patterning technique enables the fabrication of MXene‐based deformable all‐solid‐state planar MSCAs in a simple and efficient manner while achieving excellent areal performance metrics and high stretchability, making them promising micropower sources that are compatible with flexible/wearable microelectronics.

On‐Chip Microsupercapacitors: From Material to Fabrication

“…The flexible MSC exhibited an areal capacitance of 111.5 mFcm À2 and was stable in stretch, bend, and twist states, subsequently. [123] Similarly to the 3D-i-AMA stacked hybrid electrodes above, thick MXene electrodes were also demonstrated by layerby-layer stacking and laser cutting. The thickness of electrodes layer was modulated from 1.22 to 4.71 μm by varying the number of MXene layers.…”

“…Moreover, the flexible interlayer space and a large interstitial space of MXenes can accommodate more ions at a high charge/discharge rate, which would lead to good cycling and frequency response capability for the fabricated electrodes. Using different methods including bar coating, spray coating, and vacuum filtrating, MXene films were prepared and patterned on various substrates to construct on‐chip MSCs . Although MXenes exhibited high electrochemical performance, effective approaches were also reported to enhance them further as active material.…”

“…Using different methods including bar coating, spray coating, and vacuum filtrating, MXene films were prepared and patterned on various substrates to construct on-chip MSCs. [120][121][122][123] Although MXenes exhibited high electrochemical performance, effective approaches were also reported to enhance them further as active material. For example, two layers of Ti 3 C 2 T x with different flake sizes were produced as electrode materials for MSCs.…”

MXene Printing and Patterned Coating for Device Applications

“…Reproduced with permission. [ 94 ] Copyright 2019, Wiley‐VCH. h) Digital photograph showing an as‐fabricated MSC on a glass substrate, about the size of a US dime.…”

MXene‐Based Nanocomposites for Energy Conversion and Storage Applications

“…Compared with electrospun nanofibers spray‐coated with Ti 3 C 2 T x , these composite fibers exhibit high areal capacitance of 205 mF cm −2 at 50 mV s −1 . In Hu's work, the lightweight MXene/bacterial cellulose composite paper with good mechanical stability and excellent electrochemical performance was synthesized through a the solution paper‐making strategy (Figure c) . Following the simple process of laser cutting kirigami distribution, fabrication of the flexible, torsional and stretchable all solid‐state micro‐supercapacitor is carried out.…”